Synthesis of TiO2 nanosheets via an exfoliation route assisted by a surfactant

Abstract

Titanium dioxide (TiO₂) is an important material for photovoltaics, photocatalysis, sensors and lithium ion batteries. Various morphologies of TiO₂ nanomaterials have been synthesized, including zero-dimensional (0D) nanoparticles, one-dimensional (1D) nanowires and nanotubes, as well as three-dimensional (3D) nanostructures. But the two-dimensional (2D) TiO₂ nanostructures, which are expected to have more promising properties and applications, are rarely reported. Herein, we report a surfactant-assisted exfoliation method to synthesize TiO₂ 2D nanosheets. It has been revealed that tetrabutylammonium hydroxide (hereafter TBAOH) as a surfactant plays a crucial role in retaining the 2D nanosheet structures. Compared with TiO₂ nanotubes and anatase TiO₂ nanoparticles, the as-prepared TiO₂ single layered nanosheets delivered much higher capacities as anodes of the coin-type Li ion cells, with a reversible capacity of 82.2 mA h g⁻¹ at the 630th cycle at a current density of 2000 mA g⁻¹.